Conventional backup systems copy electronic files from primary storage (e.g., a high speed data storage array) to secondary storage (e.g., disks, tapes, etc.). For example, during a full backup routine, all files are copied from primary storage to secondary storage. Additionally, during an incremental backup routine, all files which have changed or which have been created since the last backup are copied from primary storage to secondary storage. Since secondary storage often resides at a remote location, the backup files of each backup routine are typically stored in encrypted form thus preventing unauthorized users from accessing the information on the backup files.
Similarly, conventional archive systems copy electronic files from primary storage to secondary storage. However, once the copies of the files reach secondary storage, the original files are removed from primary storage to recapture primary storage resources. For example, during an archive routine, all files residing on a particular volume, or older than a certain date, are transferred onto secondary storage thus freeing up primary storage disk space, backup resources, etc. for use on other files. Again, since secondary storage often resides at an offsite location, the archive files of each archive process are typically stored in encrypted form thus preventing unauthorized users from accessing the information on the archive files.
Retrieval of backup or archive files from the secondary storage system typically involves manual activity by a system technician or manager. Often, the technician must retrieve a subset of files from a larger set, but does not know up front just which files are relevant. For example, suppose that the secondary storage system receives and stores files from multiple different client computers as part of a particular backup or archive routine. Furthermore, for security purposes, suppose that the data on these files was encrypted by the client computers prior to being sent from the client computers to the secondary storage system.
To retrieve files relating to certain information (e.g., files relating to “Company ABC”), the technician enters one or more commands to the secondary storage system to retrieve all of the files from the particular backup or archive routine. The secondary storage system responds to these commands by decrypting all of the files which were backed up or archived during that particular backup or archive routine and storing decrypted copies of all of the files in a designated location. The technician is then able to manually navigate through the decrypted copies of all of the files (e.g., filter, sort, manually open and read, etc.) until the technician finds the files containing that information.